Huynh Van Sa Lam

Kansas State University

Huynh Van Sa Lam
"Direct imaging of molecular structures and their ultrafast transformations in the gas phase"
September 23, 2025
4:30 p.m.
CW 103 or Zoom
Email office@phys.ksu.edu for the Zoom address

 

Abstract

Recent advances in ultrafast sciences have revolutionized our capacity to investigate physical phenomena occurring on incredibly short time scales, allowing us to observe atoms and molecules in motion within just millionths of a billionth of a second. These developments have provided unprecedented insights into fundamental molecular processes such as chemical bond breaking or formation, isomerization and electronic excitations. The field of ultrafast science has brought together many concepts and tools from physics, chemistry, and materials science, captivating broad interest from interdisciplinary scientific communities. However, despite the variety of available experimental and theoretical tools, complete and unambiguous characterization of molecular dynamics remains challenging. Even small polyatomic molecules undergo inherently complex, multidimensional motion while most measurements are indirect and low-dimensional. This gap calls for highly differential measurements that can provide more direct and intuitive information. In this talk, I will describe our recent efforts to directly image molecular structures and their ultrafast transformations in the gas phase and present my view of future directions. Leveraging state-of-the-art ultrashort light sources, charged particle imaging, and data science techniques, we have been making considerable progress toward a longstanding goal in molecular optical sciences: making molecular movies tracking the motion of individual atoms within a single molecule during ultrafast structural changes with sufficient spatiotemporal resolution.